Update build images

.appveyor.yml

@@ -1,7 +1,18 @@
 #---------------------------------#
 #  Build Image                    #
 #---------------------------------#
-image: Visual Studio 2017
+image: Visual Studio 2022
+
+#---------------------------------#
+#  Install .NET                   #
+#---------------------------------#
+install:
+  - ps: $env:DOTNET_INSTALL_DIR = "$pwd\.dotnetsdk"
+  - ps: mkdir $env:DOTNET_INSTALL_DIR -Force | Out-Null
+  - ps: Invoke-WebRequest -Uri "https://dotnet.microsoft.com/download/dotnet/scripts/v1/dotnet-install.ps1" -OutFile "$($env:DOTNET_INSTALL_DIR)/dotnet-install.ps1"
+  - ps: '& "$($env:DOTNET_INSTALL_DIR)/dotnet-install.ps1" -Version 2.1.818 -InstallDir $env:DOTNET_INSTALL_DIR'
+  - ps: $env:Path = "$env:DOTNET_INSTALL_DIR;$env:Path"
+  - ps: dotnet --info
 
 #---------------------------------#
 #  Build Script                   #

azure-pipelines.yml

@@ -12,41 +12,33 @@ pr:
 jobs:
 - job: Windows
   pool:
-    vmImage: 'vs2017-win2016'
+    vmImage: 'windows-2022'
   steps:
+  - task: UseDotNet@2
+    inputs:
+      version: '2.1.x'
   - powershell: |
       $ENV:CAKE_SKIP_GITVERSION=([string]::IsNullOrEmpty($ENV:SYSTEM_PULLREQUEST_PULLREQUESTID) -eq $False).ToString()
       .\build.ps1
       exit $LASTEXITCODE 
     displayName: 'Cake Build'
 - job: macOS
   pool:
-    vmImage: 'macOS-10.14'
+    vmImage: 'macOS-11'
   steps:
-  # To manually select a Xamarin SDK version on the Hosted macOS agent, enable this script with the SDK version you want to target
-  #  https://go.microsoft.com/fwlink/?linkid=871629 
-  - bash: |
-      sudo $AGENT_HOMEDIRECTORY/scripts/select-xamarin-sdk.sh 5_18_1
-    displayName: 'Select Mono 5.18.1'
+  - task: UseDotNet@2
+    inputs:
+      version: '2.1.x'
   - bash: |
       ./build.sh
     displayName: 'Cake Build'
 - job: Ubuntu
   pool:
-    vmImage: 'ubuntu-16.04'
+    vmImage: 'ubuntu-20.04'
   steps:
-  - bash: |
-      mono --version
-    displayName: 'Show Mono version'
-  # Use Mono 6.6.0 until Cake.Recipe is compatible with Cake 0.37.0 which fixes this issue
-  - bash: |
-      sudo apt-get remove mono-complete mono-devel mono-gac mono-runtime-common monodoc-manual \
-      && sudo apt-get autoremove \
-      && echo "deb https://download.mono-project.com/repo/ubuntu stable-xenial/snapshots/6.6.0.161 main" | sudo tee /etc/apt/sources.list.d/mono-official-stable.list \
-      && sudo apt-get update \
-      && sudo apt-get install -y --no-install-recommends mono-complete \
-      && mono --version
-    displayName: 'Downgrade Mono to 6.6.0'
+  - task: UseDotNet@2
+    inputs:
+      version: '2.1.x'
   - bash: |
       ./build.sh --verbosity diagnostic
     displayName: 'Cake Build'